This invention relates to a rotary orbital sander, and more particularly to a rotary orbital sander that is adapted for use with a vacuum source.
In U.S. patent application Ser. No. 09/738,305, now U.S. Pat. No. 6,413,157 I disclosed a double action orbital sander having a sanding pad including a plurality of radially extending suction channels for drawing sanding waste through holes in a sanding disk aligned with the annular channels. Although this arrangement has been very effective for collecting and transporting loosened particles to a suction housing, I have improved upon the delivery of vacuum pressure provided through the holes in the sanding disk.
My earlier application also included a unique balancing system that uniquely balanced a pad backing and backing pad mounted on the rotatable shaft and minimized flapping of the pad backing and back up pad under the high rotational operational speed of the pad, that may be in excess of 10,000 rpm. While improving delivery of vacuum presence, I have further improved upon eliminating the flapping associated with the high speed rotation of a large diameter pad backing of a disk shape.
The present invention provides a suction ring for an orbital sander and/or a rotary orbital sander that improves upon the unobstructed flow of vacuum pressure provided through holes in a backing pad and sanding disk. In this way, the suction ring increases the delivered vacuum pressure to the sanding disk.
The present invention also provides a suction ring that improves upon the elimination of flapping associated with the high speed rotation of a disk shaped pad backing and backing pad of relatively large diameter by providing a bridge-like structure that attaches to the backing pad to work as one piece with the pad backup and backup pad.
The suction ring is provided for use with an orbital sander including a motor having a rotatable shaft with a radially off-set portion, a suction housing mounted to the motor around the motor shaft and connectable with a vacuum source for supplying vacuum pressure around the shaft, and a sanding pad assembly having a plurality of apertures therethrough.
The suction ring includes an annular frame having a circumferential side wall including first and second circumferential edges. The suction ring is disposed between the suction housing and the sanding pad assembly. One of the edges defines an opening and is adapted to mount to the sanding pad assembly. A circular back wall having an opening therein communicates the vacuum pressure from the suction housing to the orbital sanding pad assembly. The back wall is continuous with the other circumferential edge of the circumferential side wall. Sanding waste is communicated through the sanding pad passageways and suction ring to the suction housing.
In one embodiment a plurality of radially disposed ribs extends generally from the circumferential side wall to a like plurality of leg members disposed about the opening in the circular back wall, forming a bridge-like structure attached to the sanding pad assembly which includes a pad backing and back up pad. The suction ring itself is rigid and it stiffens the assembly against deformations that can occur at high rotational velocity, which is often about 10,000 rpm.
The ring may be made generally of metal or high impact plastic, and aluminum is the preferred material.
A rotary orbital sander of the invention includes a motor having a rotatable shaft with a radially off-set portion. A suction housing is mounted to the motor around the motor shaft and connectable with a vacuum source. A sanding pad assembly is mounted to the radially off-set portion of the shaft.
The sanding pad assembly further includes a backing pad having a plurality of apertures therethrough and an annular frame having a circumferential side wall including first and second circumferential edges and disposed between said suction housing and the sanding pad assembly. A circular back wall extends from one of the circumferential edges and has an opening therein sealable with the suction housing. The other circumferential edge is attached to the backing pad.
The sanding pad assembly further includes a sanding disk having a size and shape complimentary to that of the sanding pad, and a plurality of holes aligning with the apertures in the sanding pad.
A sanding pad assembly for use with a rotary orbital sander having a suction housing connectable with a vacuum source for drawing out sanding waste includes a backing pad having a periphery, a plurality of apertures extending through said backing pad, and an annular frame having a circumferential side wall attached to said backing pad and including a circumferential edge defining in part a back wall having an opening in vacuum pressure flow communication with said suction housing.
The sanding pad assembly can further include a sanding disk having a plurality of holes disposed in like fashion to the apertures in the backing pad so that the plurality of holes of the disk align with the apertures in the sanding pad assembly.
These and other features and advantages of the invention will be more fully understood from the following detailed description of the invention taken together with the accompanying drawings.